Supported procedural languages

Supported languages

You can use Cloud SQL for PostgreSQL with App Engine applications
running in the flexible environment that
are written in Java, Python, PHP, Node.js, Go, and Ruby. You can also use
Cloud SQL for PostgreSQL with external applications using the standard
PostgreSQL client-server protocol.

Connecting to Cloud SQL by using Private Google access is not supported.

Differences between Cloud SQL and standard PostgreSQL functionality

In general, the PostgreSQL functionality provided by a Cloud SQL
instance is the same as the functionality provided by a locally-hosted
PostgreSQL instance. However, there are a few differences between a
standard PostgreSQL instance and a Cloud SQL for PostgreSQL instance.

Unsupported features

Any features that require SUPERUSER privileges

An exception to this rule is made for the CREATE EXTENSION statement,
but only for supported extensions.

Custom background workers

The psql client in Cloud Shell does not support operations that
require a reconnection, such as connecting to a different database using the
\c command.

Notable differences

There are a number of PostgreSQL options and parameters that are not enabled
for editing as Cloud SQL flags.